Honestly, nothing helped me. I was nervous until May last year. It sucked and nothing I did could really take my mind off of it.
Best advice: Stay off these forums. Unless you have a specific question, don't look. Don't guess about your chances based on past offers to other pre-meds. Nothing you do now can change whether or not you will be offered an interview. And nothing you do after an interview will change whether you will get in or not.
I am not stressed at all this year. I think this comes from having gone through the process once already and also realizing that it is not the end of the world if medicine isn't where I end up in life. I explored other career options and realized that I would be fulfilled and happy in other areas and am prepared to pursue them should medicine not work out.
Try your best to keep going through life like you have been for the past few years. Try to remember that even if medicine isn't in the cards for you this year, it doesn't mean that it will never be in the cards. There are many ways to reach your goals and even if there are upsets and bumps along the way, if its what you really, really want, you will find a way to get there.
TL;DR: Keep living life. Hope for interviews, but realize that if you don't get them it's not the end of the world.
I hope my 2 cents helped.